Perhaps you should try some spelling variations:
trinh thuat » trinh luat, trinh thiet, trinh chat
trinh thuc » trinh tu, trinh thi
hang cong » dang cong, hang nong, bang cong
tong cong » trong cong, cong cong, dung cong
theo chu » theo chieu, cho chu, chao chu
chu sach » cau sach, thu sach, chieu sach
ca tap » cua tap, cac tap, va tap

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: theo chu sach - hanh ((trinh thuat) or (trinh thuc)) ((hang cong) or (tong cong)) dan ca tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo chu sach - hanh ((trinh thuat) OR (trinh thuc)) ((hang cong) OR (tong cong)) dan ca tap.
• Adding a wildcard symbol may retrieve word variants: theo chu sach - hanh ((trinh thuat) or (trinh thuc)) ((hang cong) or (tong cong)) dan ca tap*.